On December 7, Kipushi mine, with development and production works from UG 1200mL to 1590mL undertaken by KingKi Mining SAS, a subsidiary of JCHX Mining in DRC, completed the underhand LH blasting for the first time since 1996. The blasting was successfully conducted with the unprecedented application of advanced LH drilling jumbo and accurately monitoring of blastholes with gyro inclinometer, with better blasting parameter achieved than that in the design.
Kipushi project adopts sublevel open stoping method. More strict requirements were put forward to the quality of underhand LH blastholes, to achieve designed dilution & loss rates and control boulder yield within a reasonable range.The deflection tolerance at hole bottom should be ±400mm for a 20m deep hole.
The control of deflection rate and hole depth is a key challenge for LH drilling. KingKi worked out solutions to improve hole drilling accuracy via trial and error, and jumbo operators drilled holes always with the guidance of shift technicians. The deflection rate has been controlled within the allowed range after tentatively drilling 5 holes at the first slot of the first stope, and the blastholes management completely satisfied the Owner’s technical requirements, based on which the scheduled underhand drilling task in the first stope was finally finished earlier this month through the joint efforts of site foreman, operators and technicians. All drilled holes were measured qualified by the Owner’s Survey Engineer with gyro inclinometer.
With the introduction of advanced construction technology and survey equipment, mining engineers are able to make blasting operations more accurate and efficient, which not only greatly improves mining efficiency, but also achieves good results such as fewer boulders and reduced risk of pre-charging, and enhances the safety and technical reliability of this mining method.
Westhuizen, Survey Engineer at Kipushi, said: “This success is just the beginning. We will continue to work hard to explore and innovate, opening up a brighter future for the development of the mine.”
